Long chrome lug nut for bolt-thru wheel cover
Do you have a local high school with a shop program. Great teaching moment, you can youtube a video how to do it. They can weld inside of a nut and clamp and remove.
[ame="https://www.youtube.com/watch?v=aRrz-cphBY4"]Removing a broken bolt using a welder - YouTube[/ame]